Early diagnosis of pancreatic cancer is difficult, rapid progress, poor prognosis, the median survival period is only 4-6 months, the 5-year survival rate is only about 5%, and there is a king of cancer. However, early diagnosis of pancreatic cancer is difficult, alarm symptoms are atypical, tumor marker specificity is not high, and 80% of pancreatic cancer patients are already in advanced stage and inoperable at the time of diagnosis. Therefore, pancreatic cancer has become a major problem in clinical diagnosis and treatment. In recent years, the incidence rate has increased significantly. Pancreatic cancer includes pancreatic head cancer, pancreatic tail cancer, 90% of pancreatic cancer is ductal cell adenocarcinoma, and mucinous cystic adenocarcinoma and adenoid cell carcinoma are rare. Due to its special anatomical location and its own biological characteristics, more than 80% of pancreatic cancers are found in advanced stage, losing the chance of radical surgical resection and having a poor prognosis. Therefore, focusing on several important factors related to the diagnosis of pancreatic cancer may improve the early diagnosis of pancreatic cancer. First, pay close attention to alarm symptoms and high-risk factors Early clinical manifestations of pancreatic cancer lack of specificity, jaundice, abdominal pain and unexplained loss of body mass are more common symptoms, easy to be confused with gastrointestinal and liver and gallbladder diseases, coupled with the fact that some of the people in China do not have strong awareness of health care, the above early non-specific symptoms are mostly ignored by patients. Research suggests that 40% to 70% of pancreatic cancer patients have abdominal pain as the first symptom, about 10% of patients have emaciation as the first symptom, and those whose lesions are located in the head of pancreas usually have jaundice as the first symptom. Therefore, patients with unexplained weight loss, epigastric or low back pain, and sudden onset of diabetes mellitus should be highly alert to the possibility of pancreatic cancer. High-risk groups Genetic factors include family history of pancreatic cancer, hereditary pancreatitis, Peutz-Jeghers syndrome (also known as pigmented polyp syndrome), hereditary breast or ovarian tumors, familial atypical nevus melanoma, and cystic fibrosis, which have a risk of incidence that is 2 to 132 times higher than that of the general population. Non-genetic factors include smoking, age >55 years, alcohol consumption, obesity, diabetes mellitus, intraductal papillary mucinous neoplasia (IPMN), chronic pancreatitis, long-term exposure to mutagens, and hyperlipidemia. Main diagnostic methods 1. Tumor markers. Some commonly used tumor markers such as CA19-9, CA242, CA50, etc. play an important role in the diagnosis, treatment and prognosis of pancreatic cancer, but the sensitivity and specificity of these indicators are still unsatisfactory.CA19-9 is currently a more specific and widely used serum tumor marker. It is found that CA19-9 has a sensitivity of about 90% and a specificity of about 80% for the diagnosis of progressive pancreatic cancer. 2.Imaging examination is an important means to diagnose pancreatic cancer, CT, MRI, ultrasound endoscopy, positron emission computed tomography imaging have their own characteristics and advantages, and the selection should be in line with the principles of complete (displaying the whole pancreas), fine (thin-layer scanning with layer thickness of 2-3mm), dynamic (dynamic enhancement, regular follow-up), and three-dimensional (multi-axial reconstruction for a comprehensive understanding of adjoining relationships). Recommended EUS examination to diagnose pancreatic lesions 1, CT diagnostic rate of pancreatic cancer is 76%～92%, but the sensitivity for pancreatic cancer with a maximum diameter <1cm is only 33%～44%, which is poor in sensitivity! 2.Ultrasonic endoscopy has high resolution and can accurately detect pancreatic cancer with a maximum diameter of <1cm, and has been widely used as a standard procedure for pancreatic cancer diagnosis. In addition, ultrasound endoscopy can obtain cytology or histology specimens through fine needle aspiration for pathologic diagnosis. Although EUS is not yet a good solution to differentiate pancreatic cancer from chronic pancreatitis, combined with fine-needle aspiration can improve the problem. Meanwhile, it can accurately diagnose precancerous lesions of pancreatic cancer such as pancreatic intraepithelial neoplasia (PanIN), mucinous cystic neoplasm (MCN), IPMN, etc., which can be followed up closely, and at the same time, guide the timing of surgical treatment. 3.PET-CT combines the advantages of positron emission and CT, which can not only accurately display the size of the lesion and its relationship with neighboring tissues and organs, but also distinguish the benign and malignant nature of the tumor, which can help to judge whether it is suitable for surgical treatment or not, but the cost is expensive.